Wiring issues - 1976 Mustang II

Discussion in '1974 - 1978 Mustang II Talk & Tech' started by 76MustangII302, Nov 14, 2007.

  1. I have a an issue with the wiring and I know nothing about electrical. if the main power wire is attached to the solanoid on the fender well then within a couple hours the nattery is drained. does anyone know of any common issues for this year of Mustang? or do I just search until I find a short somwhere?

  2. Within a couple of hours?
    How sure are you of the battery?
    If possible I would start by trying a known good battery.

  3. If a healthy fully charged battery is discharging within a couple of hours (2? 4?) something somewhere is getting warm.

    By main power wire do you mean battery cable or fusible link? If you mean battery cable (and all the other wires) I would look at the charging system. If you mean fusible link (and all the other wires?) I would start by looking at the charging system.

    Why the charging system twice? Because the alternator is about the only thing in the car that could handle draining a healthy battery in a 'couple of hours' without being obvious. Whatever is draining the batttery is getting pretty warm, think headlight(s) level amperage and heat.

    About the only common problem with the II wiring system is a quarter century of previous owners hacking the wire loom.

    That and the wires tend to get brittle.

    Get a 1157 bulb and socket, Put it in series with each individual wire attached to the solenoid. Something draining a healthy battery in a couple of hours WILL light the bulb. That's your start point. If it comes back being the charging system you may not have to deal with the fuse box.

    Is this a I4, V6 or 8?

  4. Beat me to it.

    Yeah, couple of hours with a healthy battery is making HEAT somewhere.

    A couple of hours with a crappy battery could be radio or dome light level draw. Or no draw at all.